This invention relates to an LIF (Low Insertion Force) connector having an operating lever by which male and female connectors each having a plurality of terminals can be easily connected together and disconnected from each other.
One example of conventional LIF connectors having an operating lever is disclosed in Japanese Patent Unexamined Publication No. Hei. 7-307183.
FIGS. 4(a) and 4(b) are side views of this conventional LIF connector, showing its construction and operation.
In FIG. 4(a), a female connector 110 includes a housing 111 having a reception portion 112 for receiving a male connector 120. Horizontal grooves 113 are formed respectively through opposite side walls of the reception portion 112, and a pivot shaft 114 is formed on each of these opposite side walls, and is disposed rearwardly of the horizontal groove 113.
Guide projections 122 for being fitted respectively into the horizontal grooves 113 in the female connector 110 are formed on a housing 121 of the male connector 120.
An operating lever 130 has a U-shaped cross-section, and shaft-receiving grooves 131 are formed respectively through opposite side walls of this operating lever 130, and each of the shaft-receiving grooves 131 has a semi-circular inner (terminal) end for receiving the associated pivot shaft 114 of the female connector 110.
The pivot shafts 114 of the female connector 110 are fitted respectively into the shaft-receiving grooves 131 in the operating lever 130, and then a retaining portion 132 is secured to an inlet portion of each of the shaft-receiving grooves 131, so that the pivot shaft 114 is retained by a semi-circular abutment surface 132a of the retaining portion 132. In this manner, the operating lever 130 is pivotally mounted on the female connector 110.
An arcuate groove 133 is formed in an inner surface of each of the opposite side walls of the operating lever 130, and the arcuate groove 133 guides the associated guide projection 122 of the male connector 120, received in the horizontal groove 113 in the female connector 110, toward the inner end of this horizontal groove 113.
In the conventional LIF connector of this construction, first, the horizontal grooves 113 in the female connector 110 are positioned respectively with respect to the arcuate grooves 133 in the operating lever 130 in such a manner that the inlet of each horizontal groove 113 coincides with the associated arcuate groove 133, as shown in FIG. 4(a).
In this condition, the male connector 120 is provisionally inserted into the reception portion 112 of the female connector 110, and the guide projections 122 of the male connector 120 are guided respectively into the arcuate grooves 133 through the respective horizontal grooves 113. Then, the operating lever 130 is pivotally moved in a direction of arrow P (FIG. 4(a)).
As a result, each of the guide projections 122 is guided toward the inner ends of the associated horizontal groove 113 and arcuate groove 133, and is held in the aligned inner ends of these grooves, as shown in FIG. 4(b). As a result, the male connector 120 is completely inserted into the reception portion 112, and is fitted in the female connector 110.
However, in the above conventional LIF connector, the abutment surface 132a of the retaining portion 132 has an arcuate shape as shown in FIG. 5, and therefore the opposite ends (indicated by dots-and-dash lines in FIG. 5) of this arcuate surface are tapering, and are reduced in strength, and therefore there has been a problem that the yield of the products is low.
Another problem is that those portions (indicated by dots-and-dash lines in FIG. 5) of a mold 140 (used for molding the retaining portion 132), corresponding respectively to the opposite ends of the arcuate abutment surface 132a, are also reduced in strength.
Furthermore, since the abutment surface 132a of the retaining portion 132 is formed into an arcuate shape, the area of contact between this abutment surface 132a and the cylindrical pivot shaft 114 is large, and an increased frictional resistance is produced when pivotally moving the operating lever 130, and therefore there has been a problem that a large force is required for operating the operating lever 130.